import java.util.Objects;

public class Student extends Person{
    public String class_;
    public int id;

    public Student(String name, int age, String class_) {
        super(name, age);
        this.class_ = class_;
    }

    public Student(String class_) {
        this.class_ = class_;
    }
    public Student() {
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;
        Student student = (Student) o;
        return id == student.id && Objects.equals(class_, student.class_);
    }

    @Override
    public int hashCode() {
        return Objects.hash(class_, id);
    }
}
